Revert "sysfs, driver-core: remove unused {sysfs|device}_schedule_callback_owner()"

This reverts commit d1ba277e79889085a2faec3b68b91ce89c63f888.

Tejun writes:
        I'm sorry but can you please revert the whole series?
        get_active() waiting while a node is deactivated has potential
        to lead to deadlock and that deactivate/reactivate interface is
        something fundamentally flawed and that cgroup will have to work
        with the remove_self() like everybody else.  IOW, I think the
        first posting was correct.

Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h
index 14df05415af9..bd96c603ab6c 100644
--- a/include/linux/sysfs.h
+++ b/include/linux/sysfs.h
@@ -178,6 +178,9 @@ struct sysfs_ops {
 
 #ifdef CONFIG_SYSFS
 
+int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
+                            void *data, struct module *owner);
+
 int __must_check sysfs_create_dir_ns(struct kobject *kobj, const void *ns);
 void sysfs_remove_dir(struct kobject *kobj);
 int __must_check sysfs_rename_dir_ns(struct kobject *kobj, const char *new_name,
@@ -246,6 +249,12 @@ int __must_check sysfs_init(void);
 
 #else /* CONFIG_SYSFS */
 
+static inline int sysfs_schedule_callback(struct kobject *kobj,
+                void (*func)(void *), void *data, struct module *owner)
+{
+        return -ENOSYS;
+}
+
 static inline int sysfs_create_dir_ns(struct kobject *kobj, const void *ns)
 {
         return 0;